no oil pressure

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phaelax

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Well this sucks. 70 degrees today in ohio and a perfect day to take the Duster out. Drove to the gas station, filled up, and off I went and hopped on the highway. Windows down, music up.... then I starting getting off the highway and that's when I could hear some not so pleasant clanking noises. Glanced down at my oil gauge (mounted at bottom of dash so I couldn't readily see it without purposely looking) and that's when I saw 0. I was only on the highway for about 7 miles, but who knows how far I went like this! It stalled when I pulled into the gas station and I coasted into a spot and called a tow truck.

I think it's safe to assume the pump went out, but is there anything else I should check first? Oil level on the dipstick was good and still looks clean. I'm almost afraid the engine won't start up again.
 
Did you loose a lifter. A friend just poked a pushrod through a rocker arm and the lifter came out of it'so bore and he lost oil pressure. Just a guess.
 
Well this sucks. 70 degrees today in ohio and a perfect day to take the Duster out. Drove to the gas station, filled up, and off I went and hopped on the highway. Windows down, music up.... then I starting getting off the highway and that's when I could hear some not so pleasant clanking noises. Glanced down at my oil gauge (mounted at bottom of dash so I couldn't readily see it without purposely looking) and that's when I saw 0. I was only on the highway for about 7 miles, but who knows how far I went like this! It stalled when I pulled into the gas station and I coasted into a spot and called a tow truck.

I think it's safe to assume the pump went out, but is there anything else I should check first? Oil level on the dipstick was good and still looks clean. I'm almost afraid the engine won't start up again.
Pull the oil filter and cut it open and unravel the element, check it real close...that will tell you how much further to look. Good luck.
Norm
 
Oil pump won't simply quit pumping. Either the oil pump shaft is not turning the oil pump because it broke or being as you have a big block, as toolmanmike said above, If a pushrod pierces the rocker arm, the cam can kick a lifter out of the hole and create a huge void in the oil system and you loose all oil pressure. Pull the valve covers off and check it.
 
if the engine was running with zero oil pressure, most likely either the tip of the intermediate oil pump drive shaft sheared off, or the oil pump rotor shaft broke, or what was previously mentioned: a lifter popped out of its' bore. There are some other scenarios possible. Was there any "spirited' driving involved prior to the loss of oil pressure? Or was there any engine servicing performed prior to this incident? Please give us a follow-up on what you find out.
 
if the engine was running with zero oil pressure, most likely either the tip of the intermediate oil pump drive shaft sheared off, or the oil pump rotor shaft broke, or what was previously mentioned: a lifter popped out of its' bore. There are some other scenarios possible. Was there any "spirited' driving involved prior to the loss of oil pressure? Or was there any engine servicing performed prior to this incident? Please give us a follow-up on what you find out.
we had a hemi oil pump just quit pumping one time. we caught it fairly quickly, replaced it w/ no signs of anything broken or worn. oil pressure was fine w/ a diff pump! ????
 
if an oil pump spontaneously quit pumping, and oil pressure was fine after just replacing the pump, I would first suspect a pressure relief valve stuck wide open in the first pump.
 
Well this sucks. 70 degrees today in ohio and a perfect day to take the Duster out. Drove to the gas station, filled up, and off I went and hopped on the highway. Windows down, music up.... then I starting getting off the highway and that's when I could hear some not so pleasant clanking noises. Glanced down at my oil gauge (mounted at bottom of dash so I couldn't readily see it without purposely looking) and that's when I saw 0. I was only on the highway for about 7 miles, but who knows how far I went like this! It stalled when I pulled into the gas station and I coasted into a spot and called a tow truck.

I think it's safe to assume the pump went out, but is there anything else I should check first? Oil level on the dipstick was good and still looks clean. I'm almost afraid the engine won't start up again.
The oil pump shaft is likely the culprit. You should pull it and inspect. It's fairly simple to do. 65'
 
IMO, I'm thinking a stuck relief is going to show up pretty quick after startup. For instance you start a cold engine with cold oil and peg 80 psi at first, the oil warms pretty quickly and drops to zero as the valve is stuck at 80. The valve clatter would start fairly soon I'd expect.
If not the intermediate shaft there's the possibility of a non-pinned powder metal gerotor that may have spun. Some of these are just pressed on, sometimes using nitrogen to contract the shaft a couple tenths.
Pull the distributor, the intermediate shaft, and insert a priming shaft, see what'cha got.

Difficult to see in the picture. This Melling is pinned.......

MellingPinnedGerotor.jpg
 
Pop the distributor cap off and crank the engine over with the starter... Is the rotor spinning???

---> If yes, then your intermediate shaft should be ok.... Go to next answer below...

---> If no, check the oil pump and see if the pressure relief valve is stuck...


If you shut it down before it seized, there may not be too much damage, inspect the bearings and go from there...
 
Pop the distributor cap off and crank the engine over with the starter... Is the rotor spinning???

---> If yes, then your intermediate shaft should be ok.... Go to next answer below...

---> If no, check the oil pump and see if the pressure relief valve is stuck...


If you shut it down before it seized, there may not be too much damage, inspect the bearings and go from there...
Typically, the oil pump shaft breaks below the cam drive gear. In that case your rotor will rotate but your oil pump will not. Only way to be sure is to pull the distributor remove the shaft and inspect!
 
Typically, the oil pump shaft breaks below the cam drive gear. In that case your rotor will rotate but your oil pump will not. Only way to be sure is to pull the distributor remove the shaft and inspect!
nothing to do w/ this post, just re-reading the answers. I changed my oil filter to a mopar, from a k-n last week. it has a few more pounds of oil pressure at hot idle now, I like it ! -" have to run the shortys like my 02 ram came w/ , because of shroud clearance, so I change the filter more often.
 
Took off the distributer, the end of the pump shaft looked fine as did the gears. I couldn't see any signs of damage. Pulled the valve covers noticed one was not like the other.... Where's my pushrod? Bent the hell up that's where! It's broken in the pic, I did that after pulling it out. It was nearly cracked all the way through at the bend.

Also, I wouldn't say some of the other rods looked rusty, maybe scorched a little? I'm not sure but their surfaces didn't look as clean as the one pictured.

m8MWj1k.jpg
 
Not that day, I was pretty mild with it as I was just out for a cruise. But I periodically take it out for a quick spin and will do short bursts of a bat out of hell. Nothing too prolong, much like at a strip.

The rockers looked fine, I'll have to take a closer look tomorrow. After I saw the rod, I kinda just said F* this and ate dinner. I work 12s, so chances are I won't even look tomorrow and wait for the weekend.

I'm considering just sending the car to buddy's shop and having them do a rebuild on it. Might sound like overkill, but I'd rather them do a full inspection on it at this point than me fiddling around with the knowledge of a few youtube videos.
 
possibly bad rocker geometry? OEM stamped rockers or cast rockers? milled heads w/ now too long pushrods? too tight or galled valve guides? valve spring coil bind? it will be interesting to see what turns up. keep us posted.
 
Not that day, I was pretty mild with it as I was just out for a cruise. But I periodically take it out for a quick spin and will do short bursts of a bat out of hell. Nothing too prolong, much like at a strip.

The rockers looked fine, I'll have to take a closer look tomorrow. After I saw the rod, I kinda just said F* this and ate dinner. I work 12s, so chances are I won't even look tomorrow and wait for the weekend.

I'm considering just sending the car to buddy's shop and having them do a rebuild on it. Might sound like overkill, but I'd rather them do a full inspection on it at this point than me fiddling around with the knowledge of a few youtube videos.

Take some pictures of the engine with the valve covers off so we can see what you have and give some input...
 
Went ahead and pulled the valley pan off this evening. The lifter was just sort of sitting there.
IMG_6076.JPG



Far as I can tell, it looks fine with a smooth surface.
IMG_6075.JPG




2nd rocker from the end is where the rod bent if you can't see the missing one
IMG_6077.JPG



Here's the oil pump shaft and gear
IMG_6079.JPG



Other than the pushrod, everything else appears to be intact. I saw no scoring or marks on the lifter or camshaft. Other than some oily gunked, pieces of which could've been from the rtv as I pulled things off. But you'll notice how stuff looks rusty.

Full size pics are here:
purpletoken.com/broken/
 
Only thing I could find on the rocker was a very tiny scratch located where I circled (generic pic). The lifter fit back in perfectly. Slides smoothly, no side to side play.

312-P4529476.jpg
 
Only thing I could find on the rocker was a very tiny scratch located where I circled (generic pic). The lifter fit back in perfectly. Slides smoothly, no side to side play.

View attachment 1715032797

I think some are just ground from the factory there, I just got gone cleaning mine up (serious sludge) and a few of mine have what I believe can only be factory (or otherwise intentional) grinds there. Not all, but some.
 
Only thing I could find on the rocker was a very tiny scratch...........
Take a good look between the shaft area and the socket for any clues that may have cause the rod to bend.

Maybe it was slightly bent when installed or fatigued and did a slow death? I'd question the other 15 at this point. Can't imagine the intake valve hanging in the guide. Spring and damper still intact? What cam is in there?
Lol, Is it an optical conclusion on my part or is that a tapered end on the top of pushrod #8 exh?
upload_2017-3-28_18-31-55.png
 
Take a good look between the shaft area and the socket for any clues that may have cause the rod to bend.

Maybe it was slightly bent when installed or fatigued and did a slow death? I'd question the other 15 at this point. Can't imagine the intake valve hanging in the guide. Spring and damper still intact? What cam is in there?
Lol, Is it an optical conclusion on my part or is that a tapered end on the top of pushrod #8 exh?
View attachment 1715032802
Didn't notice that myself, but that does look taperd.....weird.
 
Pretty sure they were all straight, but I'll inspect that one closer. Probably just how the camera caught it.

Since it was severely cracked, is it possible the crack formed first from a manufacturing defect which weakened that point in the rod and eventually bent?
 
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